Synonyms of unlawful

2 Syllables
banned, pricey, unfair, wrongful, taboo, lawless, amiss, no-no, bootleg, pricier
3 Syllables
improper, villainous, criminal, unsporting, pirated, overkill, flagitious, black-market, forbidden, bootlegged, outlawed, illicit, illegal, nefarious
4 Syllables
unlicensed, unapproved, prohibited, extralegal, iniquitous, misbegotten, indictable, unreasoned, actionable
5 Syllables
unauthorized, under-the-counter
6 Syllables
illegitimate, unconstitutional